The proposed study will help fill critical gaps in the understanding of how bacterial STIs may impact mother-to-child-transmission (MTCT) of HIV infection and infant morbidity and mortality in the era of combination antiretroviral therapy in pregnant women. We propose a study to investigate screening for Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections, and the potential impact of a screening program on the MTCT of HIV infection. Recent research by our group, including in South Africa, has demonstrated that NG and CT infections doubled the risk of mother-to-child HIV transmission. South Africa's estimated preterm delivery rate of 8 per 100 live-births results in more than 80,000 preterm births annually, associated with about 60% infant mortality. With one of the largest numbers of HIV-infected pregnant women delivering annually in the world (>300,000), both adverse birth outcomes and HIV MTCT are significant public health problems; despite this, few studies have systematically measured the role of STIs and adverse birth outcomes in HIV-infected South African women. There are two specific aims to our proposal. Aim 1: We will determine the acceptability and feasibility of screening and treating HIV-infected pregnant women for NG and CT at first antenatal care visit, in order to: a) determine the proportion of eligible women consenting to testing (acceptability) and NG/CT-infected women receiving treatment within two weeks of specimen collection (feasibility), b) estimate the prevalence of CT and NG in HIV-infected pregnant women in Tshwane District, South Africa; and c) examine correlates of CT and/or NG infection and CT/NG treatment outcomes among pregnant women in the study. Aim 2: We will describe longitudinal birth and infant outcomes for HIV-infected pregnant women screened for CT and NG, in order to: a) estimate the frequency of adverse birth outcomes and their association with CT and NG screening and treatment; and b) estimate the frequency of HIV MTCT and its association with CT and NG screening and treatment. This pilot study is designed to determine the feasibility and acceptability of routinizing CT/NG screening and treatment of HIV-infected pregnant women, including treatment of partners to prevent re-infection. It has the potential to significantly inform programs aimed at the prevention of HIV MTCT in South Africa and to directly impact clinical and public health practices in low and middle-income countries relating to maternal-child health, especially relating to bacterial STIs.